buffer-string obsolete

[EdHamilton9]

Hi. Thank you for the nice package. It works well and does what I need.
I am posting this as an issue, not a pull request, because I am very new to emacs - 1 month or so. Also I do not write code and have never submitted a pull request.

I am using emacs 30.0.50.

mw-thesaurus.el will run if I load it into a buffer and evaluate the buffer.
It will not compile. The error message is mw-thesaurus.el:178:20: Warning: ‘buffer-string’ is an obsolete
generalized variable.
I Googled a few things and found this page:
https://github.com/emacs-mirror/emacs/blob/master/lisp/emacs-lisp/gv.el
lines 657 to 659 seem to say that the replacement is 'erase-buffer'.
It looks like the change happened in version 29.1

I replaced the code on your line 178 with (erase-buffer) and the package compiled and ran.